"Have any of you ever seen a Select (just a select no select for update)
take out a Table Exclusive lock (TX) ? we had one in SAP this morning on
ZPICK01 and the developers assure me that the transaction doesn't try to
update the table. The only thing I can think of, is that ZPICK01 is huge
and that Oracle tried to ensure some form of Read Consistency by making
the table TX. That said I'm still not certain that some switch in the
transaction isn't set to lock the table. Thoughts ?"

Gee, I haven't worked much on SAP lately, but I believe tables prefixed
Y and Z are custom tables, although I don't see why that would make a
difference.